you dont really have much choice with a 30l tank, some people will disagree with this though. i would advise to get a bigger tank adn you can have much more selection depending on the size of the tank.
i got a good picture well sort of the fish is just turning so you see three quarters sort of the patches. the good thing though the patches seem to be darker so you can see where they are if you zoom in they are a bit lighter then that colour you see in the photo though
wow how do you do that its a really good shot. im going to try use my sisters fancy camera instead of my old crappy one but the problem is the murrays light up its weird but when i have the camera on them and you can see it through the screen on the camera and they light up shining which blocks you from seeing anything the reds dont do this though but ill go try taking the phot with no lights on.
ok you need water readings for a ammonia nitrate nitrite and Ph. need to know what type of tank you have so how big and what filter you used. also need to know if you are using a dechlorinator,and if you cycled the tank.
a bowl is not big enough to keep a goldfish in also they need about 10 to 15 gallons(UK) each it think.